From 6451fe73fa0f542a49bfacd7205b88a597897f58 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Sun, 9 Dec 2018 11:21:45 -0700 Subject: [PATCH] nvme: fix irq vs io_queue calculations Guenter reported an boot hang issue on HPPA after we default to 0 poll queues. We have two issues in the queue count calculations: 1) We don't separate the poll queues from the read/write queues. This is important, since the former doesn't need interrupts. 2) The adjust logic is broken. Adjust the poll queue count before doing nvme_calc_io_queues(). The poll queue count is only limited by the IO queue count we were able to get from the controller, not failures in the IRQ allocation loop. This leaves nvme_calc_io_queues() just adjusting the read/write queue map. Reported-by: Reported-by: Guenter Roeck Reviewed-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Signed-off-by: Jens Axboe --- drivers/nvme/host/pci.c | 64 ++++++++++++++++++++++--------------------------- 1 file changed, 29 insertions(+), 35 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 7732c49..fb9d827 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -2030,60 +2030,40 @@ static int nvme_setup_host_mem(struct nvme_dev *dev) return ret; } -static void nvme_calc_io_queues(struct nvme_dev *dev, unsigned int nr_io_queues) +static void nvme_calc_io_queues(struct nvme_dev *dev, unsigned int irq_queues) { unsigned int this_w_queues = write_queues; - unsigned int this_p_queues = poll_queues; /* * Setup read/write queue split */ - if (nr_io_queues == 1) { + if (irq_queues == 1) { dev->io_queues[HCTX_TYPE_DEFAULT] = 1; dev->io_queues[HCTX_TYPE_READ] = 0; - dev->io_queues[HCTX_TYPE_POLL] = 0; return; } /* - * Configure number of poll queues, if set - */ - if (this_p_queues) { - /* - * We need at least one queue left. With just one queue, we'll - * have a single shared read/write set. - */ - if (this_p_queues >= nr_io_queues) { - this_w_queues = 0; - this_p_queues = nr_io_queues - 1; - } - - dev->io_queues[HCTX_TYPE_POLL] = this_p_queues; - nr_io_queues -= this_p_queues; - } else - dev->io_queues[HCTX_TYPE_POLL] = 0; - - /* * If 'write_queues' is set, ensure it leaves room for at least * one read queue */ - if (this_w_queues >= nr_io_queues) - this_w_queues = nr_io_queues - 1; + if (this_w_queues >= irq_queues) + this_w_queues = irq_queues - 1; /* * If 'write_queues' is set to zero, reads and writes will share * a queue set. */ if (!this_w_queues) { - dev->io_queues[HCTX_TYPE_DEFAULT] = nr_io_queues; + dev->io_queues[HCTX_TYPE_DEFAULT] = irq_queues; dev->io_queues[HCTX_TYPE_READ] = 0; } else { dev->io_queues[HCTX_TYPE_DEFAULT] = this_w_queues; - dev->io_queues[HCTX_TYPE_READ] = nr_io_queues - this_w_queues; + dev->io_queues[HCTX_TYPE_READ] = irq_queues - this_w_queues; } } -static int nvme_setup_irqs(struct nvme_dev *dev, int nr_io_queues) +static int nvme_setup_irqs(struct nvme_dev *dev, unsigned int nr_io_queues) { struct pci_dev *pdev = to_pci_dev(dev->dev); int irq_sets[2]; @@ -2093,6 +2073,20 @@ static int nvme_setup_irqs(struct nvme_dev *dev, int nr_io_queues) .sets = irq_sets, }; int result = 0; + unsigned int irq_queues, this_p_queues; + + /* + * Poll queues don't need interrupts, but we need at least one IO + * queue left over for non-polled IO. + */ + this_p_queues = poll_queues; + if (this_p_queues >= nr_io_queues) { + this_p_queues = nr_io_queues - 1; + irq_queues = 1; + } else { + irq_queues = nr_io_queues - this_p_queues; + } + dev->io_queues[HCTX_TYPE_POLL] = this_p_queues; /* * For irq sets, we have to ask for minvec == maxvec. This passes @@ -2100,7 +2094,7 @@ static int nvme_setup_irqs(struct nvme_dev *dev, int nr_io_queues) * IRQ vector needs. */ do { - nvme_calc_io_queues(dev, nr_io_queues); + nvme_calc_io_queues(dev, irq_queues); irq_sets[0] = dev->io_queues[HCTX_TYPE_DEFAULT]; irq_sets[1] = dev->io_queues[HCTX_TYPE_READ]; if (!irq_sets[1]) @@ -2111,11 +2105,11 @@ static int nvme_setup_irqs(struct nvme_dev *dev, int nr_io_queues) * 1 + 1 queues, just ask for a single vector. We'll share * that between the single IO queue and the admin queue. */ - if (!(result < 0 && nr_io_queues == 1)) - nr_io_queues = irq_sets[0] + irq_sets[1] + 1; + if (result >= 0 && irq_queues > 1) + irq_queues = irq_sets[0] + irq_sets[1] + 1; - result = pci_alloc_irq_vectors_affinity(pdev, nr_io_queues, - nr_io_queues, + result = pci_alloc_irq_vectors_affinity(pdev, irq_queues, + irq_queues, PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY, &affd); /* @@ -2125,12 +2119,12 @@ static int nvme_setup_irqs(struct nvme_dev *dev, int nr_io_queues) * likely does not. Back down to ask for just one vector. */ if (result == -ENOSPC) { - nr_io_queues--; - if (!nr_io_queues) + irq_queues--; + if (!irq_queues) return result; continue; } else if (result == -EINVAL) { - nr_io_queues = 1; + irq_queues = 1; continue; } else if (result <= 0) return -EIO; -- 2.7.4